It was a wriggling sea worm that could turn its face inside out.

Fedortsov posted a video of the creature on Twitter, writing that he found it after a trawl. ABC reported that he often finds animals from the "twilight zone" of the sea — between 650 to 3,000 feet below the surface.

The fisherman noted the worm's strange face movements, saying he could imagine the worm wailing in a high-pitched tone.

You can hear Fedortsov's impersonation of this sound below:

In actuality, neither he or the many news outlets that covered the strange discovery were quite sure what it was — much less what kind of noise it does or doesn't make.

But its segmented wormlike body and deep-sea home could suggest that it's some type of polychaete worm. According to the Australian Museum, those ocean floor feeders have segmented bodies and bristly feet.

They're also called bristle worms.

That looks a lot like the creature that Fedortsov caught, doesn't it?

He called this 2017 catch a "beautiful creature."

ABC reported that he once told the Daily Mail that he doesn't consider his catches as creepy as some people do. "I think all fish are beautiful in their own way. I can't say that some are ugly or monstrous," he said.